A novel on-line parallel-trap supercritical fluid extraction (SFE)-high performance liquid chromatography (HPLC) system was established. The interfere consisted of automated ten-port valve and parallel traps were used to carry out continuous and alternate trapping and transferring of the sample extracted with supercritical carbon dioxide, and HPLC was used to analyze the transfer-red sample. The novel on-line system was used to monitor the extraction process of fruiting bodies of Ganoderma lucidum. The extracts of six consecutive cycles were analyzed and the optimum extraction time was determined, which accorded with the result obtained with off-line extraction. Using this system, the whole process can be monitored and the optimum extraction time can be determined with single run. In addition, it has many other advantages, such as low sample loading, high sensitivity and accuracy, short analysis time, avoiding sample pollution and easily operation etc. The system shows a great potential in the extraction and analysis of the complicated samples including traditional Chinese medicine and environmental samples etc.